I suppose it's only natural that those of us who are devotees of science fiction would like to find in it something more than a matter of idle amusement. It ought to have important significance.

On many occasions in the past I have advanced arguments for supposing such significance to exist. Here is how it goes:

The human way of life has always been subject to drastic and more or less irreversible change, usually (or, as I believe, always) mediated by some advance in science and/or technology. Thus, life is forever changed with the invention of fire-or the wheel-or agriculture-or metallurgy-or printing.

The rate of change has been continually increasing, too; for as these changes are introduced, they tend to increase the security of the human species and therefore increase its number, thus in turn increasing the number of those capable of conceiving, introducing, and developing additional advances in science and technology. Besides that, each advance serves as a base for further advance so that the effect is cumulative.

During the last two centuries, the rate of change has become so great as to be visible in the course of the individual lifetime. This has put a strain on the capacity of individuals, and societies, too, to adapt to such change, since the natural feeling always is that there should be no change. One is used to things as they are.

During the last thirty years, the rate of change has become so great as to induce a kind of social vertigo. There seems no way in which we can plan any longer, for plans become outdated as fast as they are implemented. By the time we recognize a problem, action must be taken at once; and by the time we take action, however quickly, it is too late; the problem has changed its nature and gotten away from us.

What makes it worse is that, in the course of scientific and technological advance we have reached the stage where we dispose of enough power to destroy civilization (if it is misused), or to advance it to unheard-of heights (if we use it correctly).

With stakes so high and the situation so vertiginous, what can we do?

We must learn to anticipate fairly correctly and, in making our plans, take into account not what now exists, but what is likely to exist five years hence-or ten-or twenty-whenever the solution is likely to come into effect.

But how can one take change into account correctly, when the vast mass of the population stolidly refuses to take into account the existence of any change at all? (Thus, most Americans, far from planning now for 1990, have shown by their recent actions that what they want is to see 1955 restored.)

That is where science fiction comes in. Science fiction is the one branch of literature that accepts the fact of change, the inevitability of change. Without the initial assumption that there will be change, there is no such thing as science fiction, for nothing is science fiction unless it includes events played out against a social or physical background significantly different from our own. Science fiction is at its best if the events described could not be played out at all except in a social or physical background significantly different from our own.

That doesn't mean that a science fiction story should be predictive, or that it should portray something that is going to happen, before it can be important. It doesn't even have to portray something that might conceivably happen.

The existence of change, the acceptance of change, is enough. People who read science fiction come, in time, to know that things will be different. Maybe better, maybe worse, but different. Maybe this way, maybe that way, but different.

If enough people read science fiction or are, at least, sufficiently influenced by people who read science fiction, enough of the population may come to accept change (even if only with resignation and grief) so that government leaders can plan for change in the hope of meeting something other than stolid resistance from the public. And then, who knows, civilization might survive.

And yet this is highly tenuous; and while I accept the line of reasoning thoroughly (having, as far as I know, made it up), I can see that others might dismiss it as special pleading by someone who doesn't want the stuff he writes to be dismissed as just... stuff.

Well, then, has science fiction already influenced the world? Has anything that science fiction writers have written so influenced real scientists, or engineers, or politicians, or industrialists as to introduce important changes?

What about the case of space flight, of trips to the Moon?

This has been a staple of imaginative literature since Roman times; and both Jules Verne and H.G. Wells wrote highly popular stories about trips to the Moon in the nineteenth and early twentieth centuries.

Certainly, those scientists and engineers who began to deal with rocketry realistically had read science fiction; and there is no question that men such as Robert Goddard and Werner von Braun had been exposed to such things.

This is not to say that science fiction taught them any rocketry. As a matter of fact, Wells used an anti-gravity device to get to the Moon, and Verne used a gigantic gun, and both of these devices can be dismissed out of hand as ways of reaching the Moon.

Nevertheless, they stirred the imagination, as did all the other science fiction writers who flooded into the field as the twentieth century wore on, and who began to write material in large masses (if not always in high quality). All of this prepared the minds of more and more people for the notion of such trips.

It followed that when rockets were developed as war weapons during World War II, there were not lacking engineers who saw them as devices for scientific exploration, for orbital flights, for trips to the Moon and beyond. And all this would not be laughed out of court by the general public, all the way down to the rock-bottom of the average Congressman-because science fiction had paved the way.

Even this may not seem enough-too general-too broad.

How about specific influence? How about something a specific writer has done that has influenced a specific person in such a way that the world has been changed?

That has been done, too. Consider the Hungarian physicist, Leo Szilard, who-in the middle 1930s-began thinking of the possibility of a nuclear chain reaction that might produce a nuclear bomb, who recognized that his thought had become a very real possibility when uranium fission was discovered in 1939, who moved heaven and earth to persuade Allied scientists to censor themselves voluntarily in order to keep information from reaching the Nazi enemy, who persuaded Einstein to persuade President Roosevelt to initiate a vast project for developing a nuclear bomb.

We know how that changed the world (whether for better or for worse is beside the point right now, but I certainly would not have wanted Hider to have gotten the first nuclear bomb in the early 1940s), so we can say that Leo Szilard changed it.

And how did Szilard come to have his original idea? According to Szilard himself, that idea came to him because he read a story by H. G. Wells (originally published in 1902) in which an "atomic bomb"- the phrase H. G. Wells himself used-had been featured.

Here's another case. At the present moment, industrial robots are appearing on the assembly line with increasing frequency. In Japan, whole factories are being roboticized. What's more, the robots themselves are being made more versatile, more capable, and more "intelligent" very rapidly. It isn't far- fetched to say that in a couple of decades this roboticization will be seen to have changed the face of society permanently (assuming that civilization continues to survive).

Is there anyone we can credit for this? It is difficult to place that credit on a single pair of shoulders, but perhaps the pair most likely to deserve it belongs to a man named Joseph F. Engelberger, who is the president of Unimation, which manufactures one-third of all the robots in use and has installed more of them than anybody else.

Engelberger founded his company in the late 1950s, and how do you suppose he came to found it?

Some years before, according to his own account, when he was still a college undergraduate, he became enthusiastic about the possibility of robots when he read I, Robot by Isaac Asimov.

I assure you that when I was writing my positronic robot stories back in the 1940s, my intentions were clear and simple. I just wanted to write some stories, sell them to a magazine, make a little money to pay my college tuition, and see my name in print. If I had been writing anything but science fiction, that's all that would have happened.

But I was writing science fiction-so I'm now changing the world.